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Journal of Magnesium and Alloys 2019年第4期7卷 555-565页

作者： Zeeshan ur rehman Dongjin Choi School of Materials Science and Engineering Hongik UniversitySejongRepublic of Korea

AZ91 Mg alloy was treated through a new localized PEO(Plasma Electrolytic Oxidation)coating approach,using electrolyte solutions with varying ZrO2 nanoparticles concentration(2-8 g/L)and processing *** increase in the ZrO2 concentration,several microstructural changes were observed including;formation of cluster-type structure,damage to the inner layers(∼30 min)and sealing of *** analysis of the final coatings was carried out using potentiodynamic polarization,electrochemical impedance spectroscopy and post-corrosion *** was explored that highest corrosion resistance(Rp∼81.17 kΩcm^2)of the coatings was obtained for ZrO2∼2 g/***,higher concentration of the ZrO2 nanoparticles caused weak crystalline coating structure,due to unstable and lower intensity discharges,thus failed to offer high corrosion resistance performance.

关键词： Magnesium alloy PEO coating ZrO2 Corrosion Nanoparticles addition

Power Allocation Strategy for Secret Key Generation Method in Wireless Communications

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Computers, Materials & Continua 2021年第8期68卷 2179-2188页

作者： Bin Zhang muhammad Waqas Shanshan Tu Syed Mudassir Hussain Sadaqat ur rehman School of Electronics and Information Engineering Hunan University of Science and EngineeringYongzhou425199China Engineering Research Center of Intelligent Perception and Autonomous Control Faculty of Information TechnologyBeijing University of TechnologyBeijing100124China Faculty of Computer Science and Engineering Ghulam Ishaq Khan(GIK)Institute of Engineering Sciences and TechnologyTopi23460Pakistan Department of Electronics Engineering FICTBalochistan University of Information TechnologyEngineering and Management SciencesQuetta87300Pakistan Department of Computer Science Namal InstituteMianwali42200Pakistan

Secret key generation(SKG)is an emerging technology to secure wireless communication from ***,the SKG at the physical layer is an alternate solution over traditional cryptographic methods due to wireless channels’***,the physical layer secret key generation(PHY-SKG)depends on two fundamental parameters,i.e.,coherence time and power *** coherence time for PHY-SKG is not applicable to secure wireless *** is because coherence time is for a certain period of ***,legitimate users generate the secret keys(SKs)with a shorter key length in ***,an attacker can quickly get information about the ***,the attacker can easily get valuable information from authentic ***,we considered the scheme of power allocation to enhance the secret key generation rate(SKGR)between legitimate ***,we propose an alternative method,i.e.,a power allocation,to improve the *** results show 72%higher SKGR in bits/sec by increasing power *** addition,the power transmission is based on two important parameters,i.e.,epsilon and power loss factor,as given in power transmission *** found out that a higher value of epsilon impacts power transmission and subsequently impacts the *** SKGR is approximately 40.7%greater at 250 from 50 mW at epsilon=*** value of SKGR is reduced to 18.5%at 250 mW when epsilonis ***,the transmission power is also measured against the different power loss factor values,i.e.,3.5,3,and 2.5,respectively,at epsilon=***,it is concluded that the value of epsilon and power loss factor impacts power transmission and,consequently,impacts the SKGR.

关键词： Secret key generation rate power allocation physical layer wireless communication

Energy Efficiency Trade-off with Spectral Efficiency in MIMO Systems

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Computers, Materials & Continua 2022年第3期70卷 5889-5905页

作者： Rao muhammad Asif Mustafa Shakir Jamel Nebhen Ateeq ur rehman muhammad Shafiq Jin-Ghoo Choi Department of Electrical Engineering Superior UniversityLahore54000Pakistan College of Computer Engineering and Sciences Prince Sattam Bin Abdulaziz UniversityAlkharj11942Saudi Arabia Department of Electrical Engineering Government College UniversityLahore54000Pakistan Department of Information and Communication Engineering Yeungnam UniversityGyeongsan38541Korea

5G technology can greatly improve spectral efficiency(SE)and throughput of wireless *** this regard,multiple inputmultiple output(MIMO)technology has become the most influential technology using huge antennas and user equipment(UE).However,the use of MIMO in 5G wireless technology will increase circuit power consumption and reduce energy efficiency(EE).In this regard,this article proposes an optimal solution for weighing SE and throughput tradeoff with energy *** research work is based on theWyner model of uplink(UL)and downlink(DL)transmission under the multi-cell model *** SE-EE trade-off is carried out by optimizing the choice of antenna and UEs,while the approximation method based on the logarithmic function is used for *** this paper,we analyzed the combination of UL and DL power consumption models and precoding schemes for all actual circuit power consumption models to optimize the trade-off between EE and *** simulation results show that the SE-EE trade-off has been significantly improved by developing UL and DL transmission models with the approximation method based on logarithmic *** is also recognized that the throughput-EE trade-off can be improved by knowing the total actual power consumed by the entire network.

关键词： Energy efficiency spectral efficiency throughput massive MIMO downlink uplink base stations power consumption

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藻源有机质对近海沉积物微生物群落结构影响

大连理工大学学报 2024年第5期64卷 487-494页

作者：王竞 rehman Arbaz 张宇晴岳昊李泽龙大连理工大学环境学院辽宁大连116024 辽宁省河库管理服务中心(辽宁省水文局) 辽宁沈阳110003

为研究赤潮产生的藻源有机质(AOM)对近海沉积物中微生物群落结构的影响,利用宏基因组学分析探究AOM对沉积物细菌和真菌结构的影响.结果表明,AOM降低了细菌和真菌的α多样性,并改变了细菌和真菌群落的β多样性.此外,AOM能够改变细菌和真... 详细信息

为研究赤潮产生的藻源有机质(AOM)对近海沉积物中微生物群落结构的影响,利用宏基因组学分析探究AOM对沉积物细菌和真菌结构的影响.结果表明,AOM降低了细菌和真菌的α多样性,并改变了细菌和真菌群落的β多样性.此外,AOM能够改变细菌和真菌的组成,微生物相对丰度在不同处理中呈现显著的时间异质性.AOM的存在能够改变细菌和真菌的种间关系,增强参与AOM分解代谢微生物之间的联系,并最终导致细菌和真菌共生模式的改变.

关键词：赤潮藻源有机质群落结构宏基因组学

Modelling and Simulation of COVID-19 Outbreak Prediction Using Supervised Machine Learning

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Computers, Materials & Continua 2021年第3期66卷 2397-2407页

作者： Rachid Zagrouba muhammad Adnan Khan Atta-ur-Rahman muhammad Aamer Saleem muhammad Faheem Mushtaq Abdur rehman muhammad Farhan Khan Department of Computer Information System College of Computer Science and Information TechnologyImam Abdulrahman Bin Faisal UniversityDammam31441Saudi Arabia Department of Computer Science Riphah International UniversityLahore CampusLahore54000Pakistan Hamdard Institute of Engineering and Technology Hamdard UniversityIslamabad44000Pakistan Department of Information Technology Khwaja Fareed University of Engineering and Information TechnologyRahim Yar Khan64200Pakistan School of Computer Science NCBA&ELahore54000Pakistan Department of Forensic Sciences University of Health SciencesLahore54000Pakistan

Novel Coronavirus-19(COVID-19)is a newer type of coronavirus that has not been formally detected in *** is established that this disease often affects people of different age groups,particularly those with body disorders,blood pressure,diabetes,heart problems,or weakened immune *** epidemic of this infection has recently had a huge impact on people around the globe with rising mortality *** levels of mortality are attributed to their transmitting behavior through physical contact between *** is extremely necessary to monitor the transmission of the infection and also to anticipate the early stages of the disease in such a way that the appropriate timing of effective precautionary measures can be *** latest global coronavirus epidemic(COVID-19)has brought new challenges to the scientific *** Intelligence(AI)-motivated methodologies may be useful in predicting the conditions,consequences,and implications of such an *** forecasts may help to monitor and prevent the spread of these *** article proposes a predictive framework incorporating Support Vector Machines(SVM)in the forecasting of a potential outbreak of *** findings indicate that the suggested system outperforms cutting-edge *** method could be used to predict the long-term spread of such an outbreak so that we can implement proactive measures in *** findings of the analyses indicate that the SVM forecasting framework outperformed the Neural Network methods in terms of accuracy and computational *** proposed SVM system model exhibits 98.88%and 96.79%result in terms of accuracy during training and validation respectively.

关键词： Coronavirus outbreak machine learning artificial intelligence

Physiological,transcriptome and gene functional analysis provide novel sights into cadmium accumulation and tolerance mechanisms in kenaf

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Journal of Environmental Sciences 2024年第3期137卷 500-514页

作者： Shan Cao Meng Wang Jiao Pan Dengjie Luo Samavia Mubeen Caijin Wang Jiao Yue Xia Wu Qijing Wu Hui Zhang Canni Chen Muzammal rehman Sichen Xie Ru Li Peng Chen Guangxi Key Laboratory of Agro-environment and Agric-products safety Key Laboratory of Plant Genetics and BreedingCollege of AgricultureGuangxi UniversityNanning 530004China State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources College of Life Science and TechnologyGuangxi UniversityNanning 530004China

Kenaf is considered to have great potential for remediation of heavy metals in ***,studies on molecular mechanisms of root Cd accumulation and tolerance are still *** this study,two differently tolerant kenaf cultivars were selected as materials and the physiological and transcriptomic effects were evaluated under Cd *** study showed that 200μmol/L CdCl_(2) treatment triggered the reactive oxygen species(ROS)explosion and membrane lipid *** with the Cd-sensitive cultivar‘Z',the Cd-tolerant cultivar‘F'was able to resist oxidative stress in cells by producing higher antioxidant enzyme activities and increasing the contents of ascorbic acid(AsA)and glutathione(GSH).The root cell wall of‘F'exhibited higher polysaccharide contents under Cd treatment,providing more Cd-binding *** were 3,439 differentially expressed genes(DEGs)that were co-regulated by Cd treatment in two *** biosynthesis and plant hormone signal transduction pathways were significantly enriched by functional annotation *** associated with pectin,cellulose,and hemi-cellulose metabolism were involved in Cd chelation of root cell wall;V-ATPases,ABCC3 and Narmp3 could participated in vacuolar compartmentalization of Cd;PDR1 was responsible for Cd effux;the organic acid transporters contributed to the absorption of Cd in *** genes might have played key roles in kenaf Cd tolerance and Cd ***,HcZIP2 was identified to be involved in Cd uptake and transport in *** findings provide a deeper understanding of the molecular pathways underlying Cd accumulation and detoxification mechanisms in kenaf.

关键词： Kenaf Cd stress Physiological Transcriptome HcZIP2

Bioassay studies of cobalt (Ⅱ) complexes of modified diamine

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中国化学前沿:英文版 2011年第2期6卷 98-104页

作者： Saeed-ur-rehman muhammad IKRAM Sadia rehman Shah NAWAZ Institute of Chemical Sciences University of PeshawarPeshawar 25120Pakistan

Coordination compounds of modified diamine,the basic unit of which are ethylenediamine,with that of Co(Ⅱ)are *** modified diamines are ethylenediaceticacid(EDDA)and N,N,N,N-tetaraethylene-1,2-diamine(TEEDA).These diamines are characterized through ^(1)H-NMR,^(13)C-NMR,elemental analysis and IR ***(Ⅱ)complexes of these two ligands were prepared and characterized by physical measurements including elemental analysis,IR,UVVisible,magnetic susceptibilities and conductance *** activities are also carried out in order to investigate the biological activity upon *** were screened against four pathogenic bacteria like Escherichia coli,Pseudomonas aeroginosa,Klesbella pneumonia and Staphylococcus *** results showed significant enhancement in activities.

关键词： EDDA TEEDA cobalt complexes antibacterial studies

Numerical Study of Computer Virus Reaction Diffusion Epidemic Model

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Computers, Materials & Continua 2021年第3期66卷 3183-3194页

作者： Umbreen Fatima Dumitru Baleanu Nauman Ahmed Shumaila Azam Ali Raza muhammad Rafiq muhammad Aziz-ur rehman Department of Computer Science The University of LahoreLahorePakistan Department of Mathematics Cankaya UniversityAnkaraTurkey Institute of Space Sciences Magurele-BucharestRomania Department of Medical Research China Medical University HospitalChina Medical UniversityTaichungTaiwan Department of Mathematics and Statistics The University of LahoreLahorePakistan Department of Mathematics National College of Business Administration and Economics LahoreLahorePakistan Faculty of Engineering University of Central PunjabLahorePakistan Department of Mathematics University of Management and TechnologyLahorePakistan

Reaction–diffusion systems are mathematical models which link to several physical *** most common is the change in space and time of the meditation of one or more ***–diffusion modeling is a substantial role in the modeling of computer propagation like infectious *** investigated the transmission dynamics of the computer virus in which connected to each other through network *** current study devoted to the structure-preserving analysis of the computer propagation *** manuscript is devoted to finding the numerical investigation of the reaction–diffusion computer virus epidemic model with the help of a reliable *** designed technique is finite difference scheme which sustains the important physical behavior of continuous model like the positivity of the dependent variables,the stability of the *** theoretical analysis of the proposed method like the positivity of the approximation,stability,and consistency is discussed in detail.A numerical example of simulations yields the authentication of the theoretical results of the designed technique.

关键词： Computer virus dynamics reaction-diffusion system positive solution simulations

An Efficient Impersonation Attack Detection Method in Fog Computing

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Computers, Materials & Continua 2021年第7期68卷 267-281页

作者： Jialin Wan muhammad Waqas Shanshan Tu Syed Mudassir Hussain Ahsan Shah Sadaqat ur rehman muhammad Hanif Engineering Research Center of Intelligent Perception and Autonomous Control Faculty of Information TechnologyBeijing University of TechnologyBeijing100124China Faculty of Computer Science and Engineering Ghulam Ishaq Khan Institute of Engineering Sciences and TechnologyTopi23460Pakistan Department of Electronics Engineering FICTBalochistan University of Information TechnologyEngineering and Management SciencesQuetta87300Pakistan Department of Computer Science Namal InstituteMianwali42200Pakistan

Fog computing paradigm extends computing,communication,storage,and network resources to the network’s *** the fog layer is located between cloud and end-users,it can provide more convenience and timely services to ***,in fog computing(FC),attackers can behave as real fog nodes or end-users to provide malicious services in the *** attacker acts as an impersonator to impersonate other legitimate ***,in this work,we present a detection technique to secure the FC ***,we model a physical layer key generation based on wireless channel *** generate the secret keys between the legitimate users and avoid impersonators,we then consider a Double Sarsa technique to identify the impersonators at the receiver *** compare our proposed Double Sarsa technique with the other two methods to validate our work,i.e.,Sarsa and *** simulation results demonstrate that the method based on Double Sarsa outperforms Sarsa and Q-learning approaches in terms of false alarm rate(FAR),miss detection rate(MDR),and average error rate(AER).

关键词： Fog computing double Sarsa attack detection physical layer key security

Electron doping induced semiconductor to metal transitions in ZrSe2 layers via copper atomic intercalation

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Nano Research 2018年第9期11卷 4914-4922页

作者： Zahir muhammad Kejun Mu Haifeng Lv Chuanqiang Wu Zia ur rehman muhammad Habib Zhe Sun Xiaojun Wu Li Song National Synchrotron Radiation Laboratory CAS Center for Excellence in Nanoscience CAS Key Laboratory of Strongly-coupled Quantum Matter Physics University of Science and Technology of China Hefei 230029 China CAS Key Laboratory of Materials for Energy Conservation Synergetic Innovation Centre of Quantum Information & Quantum Physics CAS Center for Excellence in Nanoscience and Department of Material Science and Engineering University of Science and Technology of China Hefei 230026 China

Atomic intercalation in two-dimensional （2D） layered materials can be used to engineer the electronic structure at the atomic scale and generate tuneable physical and chemical properties which are quite distinct in comparison with the pristine material. Among them, electron-doped engineering induced by intercalation is an efficient route to modulate electronic states in 2D layers. Herein, we demonstrate a semiconducting to metallic phase transition in zirconium diselenide （ZrSe2） single crystals via controllable incorporation of copper （Cu） atoms. Our angle resolved photoemission spectroscopy （ARPES） measurements and first-principles density functional theory （DFT） calculations dearly revealed the emergence of conduction band dispersion at the M/L point of the Brillouin zone due to Cu-induced electron doping in ZrSe2 interlayers. Moreover, electrical measurements in ZrSe2 revealed semiconducting behavior, while the Cu-intercalated ZrSe2 exhibited a linear current-voltage curve with metallic character. The atomic intercalation approach may have high potential for realizing transparent electron-doping systems for many specific 2D-based nanoelectronic applications.

关键词： layered materials phase transition angle resolved photoemission spectroscopy electron doping